On occasion, when I have a PPP connection up, I get the following message
on the console (often repeatedly):

/netbsd: zstty0: ring overrun


Due to a variety of tests that are not all worth describing, I suspect
that the cause of this is that the port speed on tty0 doesn't match the
modem's speed.  I have a 33.6 modem, but I couldn't get pppd to start with
the baud rate set at 33600.  Setting it at 38400 worked, so I've been
going with that.


I'm curious as to what "ring overrun" means, and what its consequences
are.  Does it mean that the OS has overflowed the modem's buffer, or
something like that?  And is there anything I can change so that this
error won't be reported? 


Thanks for any advice,

Brian